1. Field of the Invention
The present invention relates to a projector. More particularly, the present invention relates to a color wheel of a projector.
2. Description of Related Art
Generally, a digital light processing (DLP) projection device includes an illumination system, a digital micro-mirror device (DMD), and a projection lens. The illumination system, capable of providing an illuminating light beam, includes a color wheel and a plurality of lenses. After being filtered by the color wheel, the light beam is focused by the lenses and projected onto the DMD. The DMD has a plurality of micro-mirrors, which are in ON, OFF, or FLAT states respectively, so as to convert the illuminating light beam into an image light beam. The projection lens is used to project the image light beam onto a screen to form an image.
Referring to FIG. 1, a conventional color wheel 100 includes a ring filter 110, a washer 120, and a motor 130. The ring filter 110 is formed by arranging a plurality of sector sub-filters 112, and each of the sub-filters 112 is adhered on the motor 130 by dispensing. The joints between the sub-filters 112 are not adhered. The washer 120 is located above the ring filter 110 and is adhered to the motor 130 by dispensing. However, since it is difficult to control the quality of the adhesive, and the adhesive is easily deteriorated and carbonized after a long-time operation of the motor 130, the sub-filters 112 are likely to come loose and escape when the motor 130 is rotated at a high speed.
In addition, U.S. Pat. No. 6,504,598 and ROC Patent No. 534329 also provide solutions for the problem that the sub-filters may easily come loose and escape when the motor 130 is rotated at a high speed, but each of the solutions must employ an adhesive to achieve the purpose. For example, in the ROC Patent No. 534329, an adhesive material is coated on the two sides of the filter, and in the U.S. Pat. No. 6,504,598, an adhesive of epoxy resin is used to adhere the outer margin of the filter to the inner margin of a circumferential ring. Therefore, the problem that the adhesive is easily deteriorated and carbonized still exists.